U.S. patent application number 10/036573 was filed with the patent office on 2003-07-03 for mechanical fastening system for an absorbent article.
This patent application is currently assigned to Kimberly-Clark Worldwide, Inc.. Invention is credited to Durrance, Debra, Linker, Paul M., Morman, Michael T., Popp, Robert L., VanGompel, Paul.
Application Number | 20030125703 10/036573 |
Document ID | / |
Family ID | 21889352 |
Filed Date | 2003-07-03 |
United States Patent
Application |
20030125703 |
Kind Code |
A1 |
Popp, Robert L. ; et
al. |
July 3, 2003 |
Mechanical fastening system for an absorbent article
Abstract
An absorbent article such as infant diapers is provided with a
mechanical hook-and-loop type fastening system in which the loop
material comprises an oriented nonwoven material.
Inventors: |
Popp, Robert L.;
(Hortonville, WI) ; Durrance, Debra; (Appleton,
WI) ; VanGompel, Paul; (Hortonville, WI) ;
Morman, Michael T.; (Alpharetta, GA) ; Linker, Paul
M.; (Appleton, WI) |
Correspondence
Address: |
SENNIGER POWERS LEAVITT AND ROEDEL
ONE METROPOLITAN SQUARE
16TH FLOOR
ST LOUIS
MO
63102
US
|
Assignee: |
Kimberly-Clark Worldwide,
Inc.
|
Family ID: |
21889352 |
Appl. No.: |
10/036573 |
Filed: |
December 31, 2001 |
Current U.S.
Class: |
604/391 |
Current CPC
Class: |
Y10T 29/49826 20150115;
A61F 13/15756 20130101; A61F 13/15707 20130101; A44B 18/0003
20130101; A61F 13/627 20130101; Y10T 156/10 20150115; Y10T
428/24008 20150115 |
Class at
Publication: |
604/391 |
International
Class: |
A61F 013/15 |
Claims
What is claimed is:
1. A mechanical fastening system for an article, comprising: a
first fastening component comprising an oriented nonwoven loop
material disposed on an article, the oriented nonwoven loop
material comprising a nonwoven web and produced by application of a
force causing constituent fibers of the nonwoven web to become
oriented in a direction of the applied force without substantial
necking or gathering of the nonwoven web in a direction
perpendicular to the applied force; and a second fastening
component comprising a hook material disposed on the article and
adapted to engage the first fastening component.
2. The mechanical fastening system of claim 1 wherein the first
fastening component has been stabilized by laminating the oriented
nonwoven loop material to an elastomeric material to provide
elastic properties to the resulting composite.
3. The mechanical fastening system of claim 1 wherein constituent
fibers of the nonwoven web are oriented in the machine
direction.
4. The mechanical fastening system of claim 1 wherein constituent
fibers of the nonwoven web are oriented in the cross machine
direction.
5. The mechanical fastening system of claim 1 wherein the first
fastening component has been stabilized by thermally treating the
material.
6. A mechanical fastening system for an article, comprising: a
first fastening component comprising an oriented nonwoven loop
material disposed on an article, the oriented nonwoven loop
material comprising a nonwoven web and produced by application of a
force causing constituent fibers of the nonwoven web to become
oriented in a direction of the applied force, the first fastening
component having been stabilized by laminating the oriented
nonwoven loop material to an inelastic material; and a second
fastening component comprising a hook material disposed on the
article and adapted to engage the first fastening component.
7. The mechanical fastening system of claim 6 wherein constituent
fibers of the nonwoven web become oriented in the direction of the
force without substantial necking or gathering of the nonwoven web
in the direction perpendicular to the applied force.
8. A mechanical fastening system of claim 6 wherein constituent
fibers of the nonwoven web become oriented in the direction of the
force with concomitant necking or narrowing of the nonwoven web in
the direction perpendicular to the applied force.
9. The mechanical fastening system of claim 6 wherein nonwoven web
is formed of substantially continuous fibers.
10. The mechanical fastening system of claim 6 wherein constituent
fibers of the nonwoven web are oriented in the machine
direction.
11. The mechanical fastening system of claim 6 wherein constituent
fibers of the nonwoven web are oriented in the cross machine
direction.
12. A disposable absorbent article for personal wear, comprising: a
body having first and second end regions and comprising a liquid
permeable inner layer for contact with the wearer's skin, an outer
layer in opposed relation with the inner layer, and an absorbent
layer disposed between the inner layer and the outer layer; and a
mechanical fastening system comprising first and second fastening
components disposed in the respective first and second end regions
and adapted to refastenably secure the body in a pant
configuration, the first fastening component formed of an oriented
nonwoven loop material comprising a nonwoven web, the oriented
nonwoven loop material produced by application of a force causing
constituent fibers of the nonwoven web to become oriented in a
direction of the applied force without substantial necking or
gathering of the nonwoven web in a direction perpendicular to the
applied force, and the second fastening component comprising a hook
material.
13. The disposable absorbent article of claim 12 wherein the first
fastening component has been stabilized by laminating the oriented
nonwoven loop material to an inelastic material.
14. The disposable absorbent article of claim 12 wherein the first
fastening component has been stabilized by laminating the oriented
nonwoven loop material to an elastomeric material to provide
elastic properties to the resulting composite.
15. A disposable absorbent article for personal wear, comprising: a
body having first and second end regions and comprising a liquid
permeable inner layer for contact with the wearer's skin, an outer
layer in opposed relation with the inner layer, and an absorbent
layer disposed between the inner layer and the outer layer; and a
mechanical fastening system comprising first and second fastening
components disposed in the respective first and second end regions
and adapted to refastenably secure the body in a pant
configuration, the first fastening component formed of an oriented
nonwoven loop material comprising a nonwoven web, the oriented
nonwoven loop material produced by application of a force causing
constituent fibers of the nonwoven web to become oriented in a
direction of the applied force, the first fastening component being
extensible and bonded in overlaying relationship onto a layer of
the body to retain extension and retraction characteristics of
oriented nonwoven loop material, and the second fastening component
comprising a hook material.
16. The disposable absorbent article of claim 15 wherein the first
fastening component has been stabilized by laminating the oriented
nonwoven loop material to an elastomeric material to provide
elastic properties to the resulting composite.
17. The disposable absorbent article of claim 15 wherein the first
fastening component has been produced by orienting the nonwoven web
in the machine direction and necking the nonwoven web in the cross
machine direction.
18. The disposable absorbent article of claim 15 wherein the first
fastening component has been produced by orienting the nonwoven web
in the cross machine direction.
19. The disposable absorbent article of claim 15 wherein
constituent fibers of the nonwoven web become oriented in the
direction of the force without substantial necking or gathering of
the nonwoven web in the direction perpendicular to the applied
force.
20. A disposable absorbent article of claim 15 wherein constituent
fibers of the nonwoven web become oriented in the direction of the
force with concomitant necking or narrowing of the nonwoven web in
the direction perpendicular to the applied force.
21. The disposable absorbent article of claim 15 wherein the first
fastening component has been stabilized by thermally treating the
material.
22. A method of making a mechanical fastening system for an
article, comprising forming an oriented nonwoven loop material from
a nonwoven web of substantially continuous fibers by drawing the
nonwoven web using an applied force to align constituent fibers of
the nonwoven web without substantial necking or gathering of the
nonwoven web in a direction perpendicular to the applied force; and
disposing the drawn nonwoven web on a disposable absorbent
article.
23. The method of claim 22, further comprising treating the drawn
nonwoven web with heat.
24. method of making a mechanical fastening system for an article,
comprising forming an oriented nonwoven loop material from a
nonwoven web of substantially continuous fibers by drawing the
nonwoven web using an applied force to align the constituent fibers
of the nonwoven web, and bonding the drawn nonwoven web in
overlaying relationship onto a layer of a disposable absorbent
article to retain extension and retraction characteristics of
oriented nonwoven loop material.
25. The method of claim 24, further comprising laminating the drawn
nonwoven material to an elastic substrate, and bonding the drawn
nonwoven laminate in overlaying relationship onto the layer of the
disposable absorbent article.
26. A method of making a mechanical fastening system for an
article, comprising forming an oriented nonwoven loop material from
a nonwoven web of substantially continuous fibers by drawing the
nonwoven web using an applied force to align the constituent fibers
of the nonwoven web, laminating the oriented nonwoven loop material
to an inelastic material, and disposing the drawn nonwoven laminate
on a disposable absorbent article.
27. The method of claim 26, wherein the oriented nonwoven loop
material is laminated to an extensible, inelastic substrate.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention pertains to absorbent articles, such
as training pants, diapers, incontinence garments and the like, and
more particularly, to a mechanical fastening system for such
absorbent articles.
[0002] Such absorbent articles generally comprise a
liquid-impermeable barrier sheet, a liquid permeable body side
liner and an absorbent medium between them. They generally include
some type of attaching system for fitting the article to the
wearer. In many such applications, the fastening system is
preferably refastenable so that the article can be temporarily
removed and then refastened to the wearer.
[0003] Common forms of mechanical fastening systems are the so
called hook-and-loop systems which come in various forms and have
both advantages and disadvantages in their application to such
absorbent articles. For example, particularly with diapers, the
fasteners are secured to both sides of the garment on the front and
back thereof, generally in such a manner that the back portion of
the fasteners on each side are pulled over the front portion to
secure the garment to the wearer. In typical such products, the
loop materials are generally non-extensible and are attached to the
surface of the garment. The hook material is generally attached to
an extensible substrate so that it can be positioned on the loop
material for adjustment to the size and shape of the wearer of the
garment.
[0004] A disadvantage of this type of hook-and-loop system is the
tendency of the hooks to separate from the loop material when the
wearer is active, such as when stooping or bending as is common
with a child. This disengagement failure results in the garment
coming loose from the wearer (with possible leakage resulting) thus
requiring it to be refastened, if possible. This produces an
undesirable inconvenience and disadvantage of such a mechanical
fastening system for such applications.
[0005] Another disadvantage of this type of hook-and-loop system is
the generally high cost of the materials, which tends to constrain
the size and construction of the fastening elements used in
disposable applications and may constitute a compromise in
performance. Woven or knitted loop materials are well-known and
commonly available, but are very expensive. Nonwoven loop materials
are much less costly, but are not available widely or with a wide
range of properties or applicability.
SUMMARY OF THE INVENTION
[0006] The present invention overcomes the above-described
difficulties and disadvantages associated with such prior art
mechanical fastening systems by providing a hook-and-loop fastening
system in which the loop material is a material made of an oriented
nonwoven. The oriented non-woven can be stabilized if necessary by
laminating to another layer or by thermally setting the material.
The orientation of the nonwoven layer makes the individual fibers
of a randomly formed nonwoven align in a more parallel fashion.
This loop material can be used for making many products such as a
disposable training pant, a disposable diaper, or the like. This
loop material can be elastic or inelastic, depending on how it is
treated, combined with other materials, or applied to a
product.
[0007] Thus, one aspect of the present invention relates to
mechanical fastening systems for an article. In one embodiment, the
mechanical fastening system comprises: a first fastening component
comprising an oriented nonwoven loop material disposed on an
article, the oriented nonwoven loop material comprising a nonwoven
web and produced by application of a force causing constituent
fibers of the nonwoven web to become oriented in a direction of the
applied force without substantial necking or gathering of the
nonwoven web in a direction perpendicular to the applied force; and
a second fastening component comprising a hook material disposed on
the article and adapted to engage the first fastening
component.
[0008] In another embodiment, the mechanical fastening system
comprises: a first fastening component comprising an oriented
nonwoven loop material disposed on an article, the oriented
nonwoven loop material comprising a nonwoven web and produced by
application of a force causing constituent fibers of the nonwoven
web to become oriented in a direction of the applied force, the
first fastening component having been stabilized by laminating the
oriented nonwoven loop material to an inelastic material; and a
second fastening component comprising a hook material disposed on
the article and adapted to engage the first fastening
component.
[0009] The oriented nonwoven loop materials find particular
usefulness on disposable absorbent articles, and thus another
aspect of the invention relates to disposable absorbent articles.
In one embodiment, a disposable absorbent article for personal wear
comprises: a body having first and second end regions and
comprising a liquid permeable inner layer for contact with the
wearer's skin, an outer layer in opposed relation with the inner
layer, and an absorbent layer disposed between the inner layer and
the outer layer; and a mechanical fastening system comprising first
and second fastening components disposed in the respective first
and second end regions and adapted to refastenably secure the body
in a pant configuration, the first fastening component formed of an
oriented nonwoven loop material comprising a nonwoven web, the
oriented nonwoven loop material produced by application of a force
causing constituent fibers of the nonwoven web to become oriented
in a direction of the applied force, the first fastening component
being extensible and bonded in overlaying relationship onto a layer
of the body to retain extension and retraction characteristics of
oriented nonwoven loop material, and the second fastening component
comprising a hook material.
[0010] This invention uses an elastic or inelastic loop material
constructed from an oriented nonwoven secured directly to an
article or to an elastic or inelastic material to provide fiber
loops accessible to the hook material and with sufficient integrity
to withstand engagement. Control of the degree of orientation
and/or necking and/or addition of patterned bonds to the oriented
material can further be used to modify the material
characteristics, and thus, its engagement characteristics. For
example, by controlling the hook size and the degree of necking
independently, it is possible to produce fastening systems that
provide the above mentioned product.
[0011] Hence, the present invention also concerns method of making
mechanical fastening systems for articles. In one embodiment, a
method of making a mechanical fastening system for an article
comprises: forming an oriented nonwoven loop material from a
nonwoven web of substantially continuous fibers by drawing the
nonwoven web using an applied force to align constituent fibers of
the nonwoven web without substantial necking or gathering of the
nonwoven web in a direction perpendicular to the applied force; and
disposing the drawn nonwoven web on a disposable absorbent
article.
[0012] In another embodiment, a method of making a mechanical
fastening system for an article comprises: forming an oriented
nonwoven loop material from a nonwoven web of substantially
continuous fibers by drawing the nonwoven web using an applied
force to align the constituent fibers of the nonwoven web, and
bonding the drawn nonwoven web in overlaying relationship onto a
layer of a disposable absorbent article to retain extension and
retraction characteristics of oriented nonwoven loop material.
[0013] In a further embodiment, a method of making a mechanical
fastening system for an article comprises: forming an oriented
nonwoven loop material from a nonwoven web of substantially
continuous fibers by drawing the nonwoven web using an applied
force to align the constituent fibers of the nonwoven web,
laminating the oriented nonwoven loop material to an inelastic
material, and disposing the drawn nonwoven laminate on a disposable
absorbent article.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The above-mentioned and other features of the present
invention, and the manner of obtaining them, will become more
apparent and the invention itself will be better understood by
reference to the following description of the embodiments of the
invention taken in conjunction with the accompanying drawings,
wherein:
[0015] FIG. 1 illustrates a side view of a training pant suitable
for use with the process and apparatus according to the present
invention, where the fastening system is shown engaged on one side
of the training pant and disengaged on the other side of the
training pant.
[0016] FIG. 2 illustrates a plan view of the training pant shown in
FIG. 1 in an unfastened, stretched and laid flat condition, and
showing the surface of the training pant that faces away from the
wearer.
[0017] FIG. 3 illustrates a plan view similar to FIG. 2, but
showing the surface of the training pant that faces the wearer when
the training pant is worn, and with portions cut away to show the
underlying features.
[0018] FIG. 4 illustrates an alternative embodiment of the present
invention in a side view similar to FIG. 1.
[0019] FIG. 5 is a plan view of the embodiment of FIG. 4 in a
similar position as FIG. 3.
[0020] FIG. 6 schematically illustrates a flow diagram for
manufacture of one embodiment of the oriented nonwoven loop
material used in a pant according to the present invention. This
process would make a material oriented in the machine
direction.
[0021] FIG. 7 schematically illustrates a flow diagram for
manufacture of another embodiment of the oriented nonwoven loop
material used in a pant according to the present invention. This
would make a material oriented in the cross machine direction.
[0022] Corresponding reference characters indicate corresponding
parts throughout the drawings.
DEFINITIONS
[0023] Within the context of this specification, each term or
phrase below will include the following meaning or meanings.
[0024] "Bonded" refers to the joining, adhering, connecting,
attaching, or the like, of two elements. Two elements will be
considered to be bonded together when they are bonded directly to
one another or indirectly to one another, such as when each is
directly bonded to intermediate elements.
[0025] "Comprising" is inclusive or open-ended and does not exclude
additional, unrecited elements or method steps.
[0026] "Connected" refers to the joining, adhering, bonding,
attaching, or the like, of two elements. Two elements will be
considered to be connected together when they are connected
directly to one another or indirectly to one another, such as when
each is directly connected to intermediate elements.
[0027] "Disposable" refers to articles which are designed to be
discarded after a limited use rather than being laundered or
otherwise restored for reuse.
[0028] "Disposed," "disposed on," and variations thereof are
intended to mean that one element can be integral with another
element, or that one element can be a separate structure bonded to
or placed with or placed near another element.
[0029] "Elastic," "elasticized" and "elasticity" mean that property
of a material or composite by virtue of which it tends to recover
its original size and shape after removal of a force causing a
deformation.
[0030] "Elastomeric" refers to a material or composite which can be
elongated by at least 25 percent of its relaxed length and which
will recover, upon release of the applied force, at least 10
percent of its elongation. It is generally preferred that the
elastomeric material or composite be capable of being elongated by
at least 100 percent, more preferably by at least 300 percent, of
its relaxed length and recover, upon release of an applied force,
at least 50 percent of its elongation.
[0031] "Extensible" refers to a material or composite that is
stretchable or capable of being elongated in at least one
direction, but which may not have sufficient recovery to be
considered elastic.
[0032] "Fabrics" is used to refer to all of the woven, knitted and
nonwoven fibrous webs.
[0033] "Flexible" refers to materials which are compliant and which
will readily conform to the general shape and contours of the
wearer's body.
[0034] "Force" includes a physical influence exerted by one body on
another which produces acceleration of bodies that are free to move
and deformation of bodies that are not free to move.
[0035] "Graphic" refers to any design, pattern, or the like that is
visible on an absorbent article.
[0036] "Hydrophilic" describes fibers or the surfaces of fibers
which are wetted by the aqueous liquids in contact with the fibers.
The degree of wetting of the materials can, in turn, be described
in terms of the contact angles and the surface tensions of the
liquids and materials involved. Equipment and techniques suitable
for measuring the wettability of particular fiber materials or
blends of fiber materials can be provided by a Cahn SFA-222 Surface
Force Analyzer System, or a substantially equivalent system. When
measured with this system, fibers having contact angles less than
90 are designated "wettable" or hydrophilic, while fibers having
contact angles greater than 90 are designated "nonwettable" or
hydrophobic.
[0037] "Integral" is used to refer to various portions of a single
unitary element rather than separate structures bonded to or placed
with or placed near one another.
[0038] "Inward" and "outward" refer to positions relative to the
center of an absorbent article, and particularly transversely
and/or longitudinally closer to or away from the longitudinal and
transverse center of the absorbent article.
[0039] "Layer" when used in the singular can have the dual meaning
of a single element or a plurality of elements.
[0040] "Liquid impermeable", when used in describing a layer or
multi-layer laminate, means that a liquid, such as urine, will not
pass through the layer or laminate, under ordinary use conditions,
in a direction generally perpendicular to the plane of the layer or
laminate at the point of liquid contact. Liquid, or urine, may
spread or be transported parallel to the plane of the liquid
impermeable layer or laminate, but this is not considered to be
within the meaning of "liquid impermeable" when used herein.
[0041] "Longitudinal" and "transverse" have their customary
meaning, as indicated by the longitudinal and transverse axes
depicted in FIGS. 2 and 3. The longitudinal axis lies in the plane
of the article and is generally parallel to a vertical plane that
bisects a standing wearer into left and right body halves when the
article is worn. The transverse axis lies in the plane of the
article generally perpendicular to the longitudinal axis. The
article as illustrated is longer in the longitudinal direction than
in the transverse direction.
[0042] "Member" when used in the singular can have the dual meaning
of a single element or a plurality of elements.
[0043] "Nonwoven" and "nonwoven web" refer to materials and webs of
material which are formed without the aid of a textile weaving or
knitting process.
[0044] "Operatively joined," with reference to the attachment of an
elastic member to another element, means that the elastic member
when attached to or connected to the element, or treated with heat
or chemicals, by stretching, or the like, gives the element elastic
properties; and with reference to the attachment of a non-elastic
member to another element, means that the member and element can be
attached in any suitable manner that permits or allows them to
perform the intended or described function of the joinder. The
joining, attaching, connecting or the like can be either directly,
such as joining either member directly to an element, or can be
indirectly by means of another member disposed between the first
member and the first element.
[0045] "Outer cover graphic" refers to a graphic that is directly
visible upon inspection of the exterior surface of a garment, and
for a refastenable garment is in reference to inspection of the
exterior surface of the garment when the fastening system is
engaged as it would be during use.
[0046] "Permanently bonded" refers to the joining, adhering,
connecting, attaching, or the like, of two elements of an absorbent
garment such that the elements tend to be and remain bonded during
normal use conditions of the absorbent garment.
[0047] "Refastenable" refers to the property of two elements being
capable of attachment, separation, and subsequent reattachment.
[0048] "Releasably attached," "releasably engaged" and variations
thereof refer to two elements being connected or connectable such
that the elements tend to remain connected absent a separation
force applied to one or both of the elements, and the elements
being capable of separation without substantial permanent
deformation or rupture. The required separation force is typically
beyond that encountered while wearing the absorbent garment.
[0049] "Necked material" refers to a material that has been
extended under mechanical force in one direction substantially
beyond its tensile yield point in that direction in a manner that
narrows, or "necks" the material in the direction perpendicular to
the direction of the applied force so that the material does not
tend to recover to its original width dimension.
[0050] "Oriented material" refers to a material in which mechanical
drawing of the material has resulted in alignment of the fibers
constituting the material in a direction generally parallel to the
direction of the applied force.
[0051] "Reversibly necked material" refers to a necked material
that has been treated while necked to impart memory to the material
so that, when a force is applied to extend the material to its
pre-necked dimensions, the necked and treated portions will
generally recover to their necked dimensions upon termination of
the force. One form of treatment is the application of heat.
Generally speaking, extension of the reversibly necked material is
substantially limited to extension to its pre-necked dimensions.
Therefore, unless the material is elastic, extension too far beyond
its pre-necked dimensions will result in material failure. A
reversibly necked material may include more than one layer, for
example, multiple layers of spunbonded web, multiple layers of
meltblown web, or any other suitable combinations or mixtures
thereof.
[0052] "Rupture" means the breaking or tearing apart of a material;
in tensile testing, the term refers to the total separation of a
material into two parts either all at once or in stages, or the
development of a hole in some materials.
[0053] "Stretch bonded" refers to an elastic member being bonded to
another member while the elastic member is extended at least about
25 percent of its relaxed length. Desirably, the term "stretch
bonded" refers to the situation wherein the elastic member is
extended at least about 100 percent, and more desirably at least
about 300-600 percent, of its relaxed length when it is bonded to
the other member.
[0054] "Stretch bonded laminate" refers to a composite material
having at least two layers in which one layer is a gatherable layer
and the other layer is an elastic layer. The layers are joined
together when the elastic layer is in an extended condition so that
upon relaxing the layers, the gatherable layer is gathered.
[0055] "Surface" includes any layer, film, woven, nonwoven,
laminate, composite, or the like, whether pervious or impervious to
air, gas, and/or liquids.
[0056] "Tension" includes a uniaxial force tending to cause the
extension of a body or the balancing force within that body
resisting the extension.
[0057] "Thermoplastic" describes a material that softens when
exposed to heat and which substantially returns to a non-softened
condition when cooled to room temperature.
[0058] These terms may be defined with additional language in the
remaining portions of the specification.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0059] FIG. 1 representatively illustrates one embodiment of
training pant 20 in a partially fastened condition. The training
pant 20 comprises an absorbent body 32 and a fastening system 80.
The absorbent body 32 defines a front waist region 22, a back waist
region 24, a crotch region 26 interconnecting the front and back
waist regions, an inner surface 28 which is configured to contact
the wearer, and an outer surface 30 opposite the inner surface
which is configured to contact the wearer's clothing. With
additional reference to FIGS. 2 and 3, the absorbent body 32 also
defines a pair of transversely opposed side edges 36 and a pair of
longitudinally opposed waist edges, which are designated front
waist edge 38 and back waist edge 39. The front waist region 22 is
contiguous with the front waist edge 38, and the back waist region
24 is contiguous with the back waist edge 39.
[0060] The illustrated absorbent body 32 comprises a rectangular
composite structure 33, a pair of transversely opposed front side
panels 34, and a pair of transversely opposed back side panels 134.
The composite structure 33 and side panels 34 and 134 may be
integrally formed or comprise two or more separate elements, as
shown in FIG. 1. The illustrated composite structure 33 comprises
an outer cover 40, a body side liner 42 (FIG. 3) which is connected
to the outer cover in a superposed relation, an absorbent assembly
44 (FIG. 3) which is located between the outer cover and the body
side liner, and a pair of containment flaps 46 (FIG. 3). The
illustrated composite structure 33 has opposite linear end edges 45
that form portions of the front and back waist edges 38 and 39, and
opposite linear side edges 47 that form portions of the side edges
36 of the absorbent body 32 (FIGS. 2 and 3). For reference, arrows
48 and 49 depicting the orientation of the longitudinal axis and
the transverse axis, respectively, of the training pant 20 are
illustrated in FIGS. 2 and 3.
[0061] With the training pant 20 in the fastened position as
partially illustrated in FIG. 1, the front and back waist regions
22 and 24 are joined together to define a three-dimensional pant
configuration having a waist opening 50 and a pair of leg openings
52. The front waist region 22 comprises the portion of the training
pant 20 which, when worn, is positioned on the front of the wearer
while the back waist region 24 comprises the portion of the
training pant which, when worn, is positioned on the back of the
wearer. The crotch region 26 of the training pant 20 comprises the
portion of the training pant which, when worn, is positioned
between the legs of the wearer and covers the lower torso of the
wearer. The front and back side panels 34 and 134 comprise the
portions of the training pant 20 which, when worn, are positioned
on the hips of the wearer.
[0062] The front waist region 22 of the absorbent body 32 includes
the transversely opposed front side panels 34 and a front center
panel 35 (FIGS. 2 and 3) positioned between and interconnecting the
side panels. The back waist region 24 of the absorbent body 32
includes the transversely opposed back side panels 134 and a back
center panel 135 (FIGS. 2 and 3) positioned between and
interconnecting the side panels. The waist edges 38 and 39 of the
absorbent body 32 are configured to encircle the waist of the
wearer when worn and provide the waist opening 50 which defines a
waist perimeter dimension. Portions of the transversely opposed
side edges 36 in the crotch region 26 generally define the leg
openings 52. The waist regions 22 and 24 jointly define a waistband
75 (FIGS. 1, 4 and 7) that peripherally surrounds the waist opening
50 of the pant 20. The waist regions 22 and 24 also jointly define
a hip section 77 (FIGS. 1, 4 and 7) that encircles the pant 20 and
is disposed between the waistband 75 and the leg openings 52.
[0063] The absorbent body 32 is configured to contain and/or absorb
any body exudates discharged from the wearer. For example, the
absorbent body 32 desirably although not necessarily comprises the
pair of containment flaps 46 which are configured to provide a
barrier to the transverse flow of body exudates. A flap elastic
member 53 (FIG. 3) is operatively joined with each containment flap
46 in any suitable manner as is well known in the art. The
elasticized containment flaps 46 define an unattached edge which
assumes an upright configuration in at least the crotch region 26
of the training pant 20 to form a seal against the wearer's body.
The containment flaps 46 can be located along the transversely
opposed side edges of the absorbent body 32, and can extend
longitudinally along the entire length of the absorbent body or may
only extend partially along the length of the absorbent body.
Suitable constructions and arrangements for the containment flaps
46 are generally well known to those skilled in the art and are
described in U.S. Pat. No. 4,704,116 issued Nov. 3, 1987 to Enloe,
which is incorporated herein by reference.
[0064] To further enhance containment and/or absorption of body
exudates, the training pant 20 desirably although not necessarily
includes a front waist elastic member 54, a rear waist elastic
member 56, and leg elastic members 58, as are known to those
skilled in the art (FIG. 3). The waist elastic members 54 and 56
can be operatively joined to the outer cover 40 and/or body side
liner 42 along the opposite waist edges 38 and 39, and can extend
over part or all of the waist edges, such that the waist elastic
members are disposed in the waistband 75 in the fully assembled
pant.
[0065] The leg elastic members 58 are desirably operatively joined
to the outer cover 40 and/or body side liner 42 along the opposite
side edges 36 and positioned in the crotch region 26 of the
training pant 20. The leg elastic members 58 can be longitudinally
aligned along each side edge 47 of the composite structure 33. Each
leg elastic member 58 has a front terminal point 63 and a back
terminal point 65, which points represent the longitudinal ends of
the elastic gathering caused by the leg elastic members. The front
terminal points 63 can be located adjacent the longitudinally
innermost parts of the front side panels 34, and the back terminal
points 65 can be located adjacent the longitudinally innermost
parts of the back side panels 134.
[0066] The flap elastic members 53, the waist elastic members 54
and 56, and the leg elastic members 58 can be formed of any
suitable elastic material. As is well known to those skilled in the
art, suitable elastic materials include sheets, strands or ribbons
of natural rubber, synthetic rubber, or thermoplastic elastomeric
polymers. The elastic materials can be stretched and adhered to a
substrate, adhered to a gathered substrate, or adhered to a
substrate and then elasticized or shrunk, for example with the
application of heat; such that elastic constrictive forces are
imparted to the substrate. In one particular embodiment, for
example, the leg elastic members 58 comprise a plurality of
dry-spun coalesced multifilament spandex elastomeric threads sold
under the trade name LYCRA and available from E. I. DuPont de
Nemours and Company, Wilmington, Del. U.S.A.
[0067] In particular embodiments, the waist elastic members 54 and
56 can be formed of retractive materials. For example, the waist
elastic members 54 and 56 can be formed of an elastomeric material
that is adapted to retract upon activation by a source of heat such
as disclosed in U.S. Pat. No. 4,640,726.
[0068] The outer cover 40 desirably comprises a material that is
substantially liquid impermeable, and can be elastic or inelastic.
The outer cover 40 can be a single layer of liquid impermeable
material, but desirably comprises a multi-layered laminate
structure in which at least one of the layers is liquid
impermeable. For instance, the outer cover 40 can include a liquid
permeable outer layer and a liquid impermeable inner layer that are
suitably joined together by laminate adhesive, ultrasonic bonds,
thermal bonds, or the like. Suitable laminate adhesives, which can
be applied continuously or intermittently as beads, a spray,
parallel swirls, or the like, can be obtained from Findley
Adhesives, Inc., of Wauwatosa, Wis. U.S.A., or from National Starch
and Chemical Company, Bridgewater, N.J. U.S.A. The liquid permeable
outer layer can be any suitable material and desirably one that
provides a generally cloth-like texture. One example of such a
material is a 20 gsm (grams per square meter) spunbond
polypropylene nonwoven web. The outer layer may also be made of an
oriented nonwoven material as provided by this invention,
constituting an integral and functional loop material covering the
entire outer surface of the cover 40. While it is not a necessity
for outer layer to be liquid permeable, it is desired that it
provides a relatively cloth-like texture to the wearer.
[0069] The inner layer of the outer cover 40 can be both liquid and
vapor impermeable, or can be liquid impermeable and vapor
permeable. The inner layer is desirably manufactured from a thin
plastic film, although other flexible liquid impermeable materials
may also be used. The inner layer, or the liquid impermeable outer
cover 40 when a single layer, prevents waste material from wetting
articles, such as bed sheets and clothing, as well as the wearer
and caregiver. A suitable liquid impermeable film for use as a
liquid impermeable inner layer, or a single layer liquid
impermeable outer cover 40, is a 0.02 millimeter polyethylene film
commercially available from Huntsman Packaging of Newport News, Va.
U.S.A. If the outer cover 40 is a single layer of material, it can
be embossed and/or matte finished providing a more cloth-like
appearance. As earlier mentioned, the liquid impermeable material
can permit vapors to escape from the interior of the disposable
absorbent article, while still preventing liquids from passing
through the outer cover 40. A suitable "breathable" material is
composed of a microporous polymer film or a nonwoven fabric that
has been coated or otherwise treated to impart a desired level of
liquid impermeability. A suitable microporous film is a PMP-1 film
material commercially available from Mitsui Toatsu Chemicals, Inc.,
Tokyo, Japan, or an XKO-8044 polyolefin film commercially available
from 3M Company, Minneapolis, Minn. U.S.A.
[0070] As shown in FIGS. 1 and 2, the training pant 20 and in
particular the outer cover 40 desirably comprises one or more
appearance-related components. Examples of appearance-related
components include, but are not limited to, graphics; highlighting
or emphasizing leg and waist openings in order to make product
shaping more evident or visible to the user; highlighting or
emphasizing areas of the product to simulate functional components
such as elastic leg bands, elastic waistbands, simulated fly
openings for boys, ruffles for girls; highlighting areas of the
product to change the appearance of the size of the product;
registering wetness indicators, temperature indicators, and the
like in the product; registering a back label, or a front label, in
the product; and registering written instructions at a desired
location in the product.
[0071] The illustrated training pant 20, which is designed for use
by young girls, includes a registered outer cover graphic 60. In
this design, the registered graphic 60 includes a primary pictorial
image 61, simulated waist ruffles 62, and simulated leg ruffles 64.
The primary pictorial image 61 includes a rainbow, sun, clouds,
animal characters, wagon and balloons. Any suitable design can be
utilized for a training pant intended for use by young girls, so as
to be aesthetically and/or functionally pleasing to them and the
caregiver. The appearance-related components are desirably
positioned on the training pant 20 at selected locations, which can
be carried out using the methods disclosed in U.S. Pat. No.
5,766,389 issued Jun. 16, 1998 to Brandon et al., which is
incorporated herein by reference. The primary pictorial image 61 is
desirably positioned in the front waist region 22 along the
longitudinal centerline of the training pant 20.
[0072] The liquid permeable body side liner 42 is illustrated as
overlying the outer cover 40 and absorbent assembly 44, and may but
need not have the same dimensions as the outer cover 40. The body
side liner 42 is desirably compliant, soft feeling, and
non-irritating to the child's skin. Further, the body side liner 42
can be less hydrophilic than the absorbent assembly 44, to present
a relatively dry surface to the wearer and permit liquid to readily
penetrate through its thickness. Alternatively, the body side liner
42 can be more hydrophilic or can have essentially the same
affinity for moisture as the absorbent assembly 44 to present a
relatively wet surface to the wearer to increase the sensation of
being wet. This wet sensation can be useful as a training aid. The
hydrophilic/hydrophobic properties can be varied across the length,
width and depth of the body side liner 42 and absorbent assembly 44
to achieve the desired wetness sensation or leakage
performance.
[0073] The body side liner 42 can be manufactured from a wide
selection of web materials, such as synthetic fibers (for example,
polyester or polypropylene fibers), natural fibers (for example,
wood or cotton fibers), a combination of natural and synthetic
fibers, porous foams, reticulated foams, apertured plastic films,
or the like. Various woven and nonwoven fabrics can be used for the
body side liner 42. For example, the body side liner can be
composed of a meltblown or spunbonded web of polyolefin fibers. The
body side liner can also be a bonded-carded web composed of natural
and/or synthetic fibers. The body side liner can also be made of an
oriented nonwoven as provided by this invention. The body side
liner can be composed of a substantially hydrophobic material, and
the hydrophobic material can, optionally, be treated with a
surfactant or otherwise processed to impart a desired level of
wettability and hydrophilicity. For example, the material can be
surface treated with about 0.45 weight percent of a surfactant
mixture comprising Ahcovel N-62 from Hodgson Textile Chemicals of
Mount Holly, N.C. U.S.A. and Glucopan 220UP from Henkel Corporation
of Ambler, Pa. in an active ratio of 3:1. The surfactant can be
applied by any conventional means, such as spraying, printing,
brush coating or the like. The surfactant can be applied to the
entire body side liner 42 or can be selectively applied to
particular sections of the body side liner, such as the medial
section along the longitudinal centerline.
[0074] A suitable liquid permeable body side liner 42 is a nonwoven
bicomponent web having a basis weight of about 27 gsm. The nonwoven
bicomponent can be a spunbond bicomponent web, or a bonded carded
bicomponent web. Suitable bicomponent staple fibers include a
polyethyene/polypropylene bicomponent fiber available from CHISSO
Corporation, Osaka, Japan. In this particular bicomponent fiber,
the polypropylene forms the core and the polyethylene forms the
sheath of the fiber. Other fiber orientations are possible, such as
multi-lobe, side-by-side, end-to-end, or the like.
[0075] The absorbent assembly 44 (FIG. 3) is positioned between the
outer cover 40 and the body side liner 42, which components can be
joined together by any suitable means such as adhesives, ultrasonic
bonds, thermal bonds, or the like. The absorbent assembly 44 can be
any structure which is generally compressible, conformable,
non-irritating to the child's skin, and capable of absorbing and
retaining liquids and certain body wastes. The absorbent assembly
44 can be manufactured in a wide variety of sizes and shapes, and
from a wide variety of liquid absorbent materials commonly used in
the art. For example, the absorbent assembly 44 can suitably
comprise a matrix of hydrophilic fibers, such as a web of cellulose
fluff, mixed with particles of a high-absorbency material commonly
known as superabsorbent material. In a particular embodiment, the
absorbent assembly 44 comprises a matrix of cellulosic fluff, such
as wood pulp fluff, and superabsorbent hydrogel-forming particles.
The wood pulp fluff can be exchanged with synthetic, polymeric,
meltblown fibers or short cut homofilament or bicomponent synthetic
fibers and natural fibers. The superabsorbent particles can be
substantially homogeneously mixed with the hydrophilic fibers or
can be nonuniformly mixed. The fluff and superabsorbent particles
can also be selectively placed into desired zones of the absorbent
assembly 44 to better contain and absorb body exudates. The
concentration of the superabsorbent particles can also vary through
the thickness of the absorbent assembly 44. Alternatively, the
absorbent assembly 44 can comprise a laminate of fibrous webs and
superabsorbent material or other suitable means of maintaining a
superabsorbent material in a localized area.
[0076] Suitable superabsorbent materials can be selected from
natural, synthetic, and modified natural polymers and materials.
The superabsorbent materials can be inorganic materials, such as
silica gels, or organic compounds, such as cross-linked polymers,
for example, sodium neutralized polyacrylic acid. Suitable
superabsorbent materials are available from various commercial
vendors, such as Dow Chemical Company located in Midland, Mich.
U.S.A., and Stockhausen GmbH & Co. KG, D47805 Krefeld, Federal
Republic of Germany. Typically, a superabsorbent material is
capable of absorbing at least about 15 times its weight in water,
and desirably is capable of absorbing more than about 25 times its
weight in water.
[0077] In one embodiment, the absorbent assembly 44 is generally
rectangular in shape, and comprises a blend of wood pulp fluff and
superabsorbent material. One preferred type of pulp is identified
with the trade designation CR1654, available from U.S. Alliance,
Childersburg, Ala. U.S.A., and is a bleached, highly absorbent
sulfate wood pulp containing primarily soft wood fibers and about
16 percent hardwood fibers. As a general rule, the superabsorbent
material is present in the absorbent assembly 44 in an amount of
from about 5 to about 90 weight percent based on total weight of
the absorbent assembly. The absorbent assembly 44 suitably has a
density within the range of about 0.10 to about 0.35 grams per
cubic centimeter. The absorbent assembly 44 may or may not be
wrapped or encompassed by a suitable tissue wrap that may help
maintain the integrity and/or shape of the absorbent assembly.
[0078] The absorbent body 32 can also incorporate other materials
that are designed primarily to receive, temporarily store, and/or
transport liquid along the mutually facing surface with absorbent
assembly 44, thereby maximizing the absorbent capacity of the
absorbent assembly. One suitable material is referred to as a surge
layer (not shown) and comprises a material having a basis weight of
about 50 to about 120 grams per square meter, and comprising a
through-air-bonded-carded web of a homogenous blend of 60 percent 3
denier type T-256 bicomponent fiber comprising a polyester
core/polyethylene sheath and 40 percent 6 denier type T-295
polyester fiber, both commercially available from Kosa Corporation
of Salisbury, N.C. U.S.A.
[0079] As noted previously, the illustrated training pant 20 has
front and back side panels 34 and 134 disposed on each side of the
absorbent body 32. These transversely opposed front side panels 34
and transversely opposed back side panels 134 can be permanently
bonded along attachment lines 66 to the composite structure 33 of
the absorbent body 32 in the respective front and back waist
regions 22 and 24. More particularly, as shown best in FIGS. 2 and
3, the front side panels 34 can be permanently bonded to and extend
transversely beyond the linear side edges 47 of the composite
structure 33 in the front waist region 22, and the back side panels
134 can be permanently bonded to and extend transversely beyond the
linear side edges of the composite structure in the back waist
region 24. The side panels 34 and 134 may be attached using
attachment means known to those skilled in the art such as
adhesive, thermal or ultrasonic bonding. Alternatively, the side
panels 34 and 134 can be formed as a portion of a component of the
composite structure 33. For example, the side panels can comprise a
generally wider portion of the outer cover, the body side liner,
and/or another component of the absorbent body.
[0080] The side panels 34 and 134 preferably have elastic
properties with sufficient extensibility to allow the wearer to
pull the product up without having to open the fasteners on the
pant. The side panels 34 and 134 also preferably provide sufficient
retraction tension at extensions normally seen during wear to
ensure good fit during wear without adjusting the fastener
position. If the outer cover 40, as described above, comprises an
elastic material, the side panels 34 and 134 may require less
extensibility. Alternately, the pant may have an all-over stretch
material across the entire width of the pant, comprising the outer
cover 40 and side panels 34 and 134 as a single material component.
The extension requirements of the side panels 34 and 134 are
determined by the desired fit range for the product and the
interaction with extension of other components, e.g., outer cover
40.
[0081] The illustrated side panels 34 and 134 each define a distal
edge 68 that is spaced from the attachment line 66, a leg end edge
70 disposed toward the longitudinal center of the training pant 20,
and a waist end edge 72 disposed toward a longitudinal end of the
training pant. The leg end edge 70 and waist end edge 72 extend
from the side edges 47 of the composite structure 33 to the distal
edges 68. The leg end edges 70 of the side panels 34 and 134 form
part of the side edges 36 of the absorbent body 32. In the back
waist region 24, the leg end edges 70 are desirably although not
necessarily curved and/or angled relative to the transverse axis 49
to provide greater coverage toward the back of the pant as compared
to the front of the pant. The waist end edges 72 are desirably
parallel to the transverse axis 49. The waist end edges 72 of the
front side panels 34 form part of the front waist edge 38 of the
absorbent body 32, and the waist end edges 72 of the back side
panels 134 form part of the back waist edge 39 of the absorbent
body.
[0082] In particular embodiments for improved fit and appearance,
the side panels 34 and 134 desirably have an average length
dimension measured parallel to the longitudinal axis 48 that is
about 20 percent or greater, and particularly about 25 percent or
greater, of the overall length dimension of the absorbent article,
also measured parallel to the longitudinal axis 48. For example, in
training pants having an overall length dimension of about 54
centimeters, the side panels 34 and 134 desirably have an average
length dimension of about 10 centimeters or greater, such as about
15 centimeters. While each of the side panels 34 and 134 extend
from the waist opening 50 to one of the leg openings 52, the back
side panels 134 have a continually decreasing length dimension
moving from the attachment line 66 to the distal edge 68, as is
best shown in FIGS. 2 and 3.
[0083] Each of the side panels 34 and 134 can include one or more
individual, distinct pieces of material. In particular embodiments,
for example, each side panel 34 and 134 can include first and
second side panel portions that are joined at a seam, or can
include a single piece of material which is folded over upon itself
(not shown). The side panels 34 and 134 desirably although not
necessarily comprise an elastic material capable of stretching in a
direction generally parallel to the transverse axis 49 of the
training pant 20. Suitable elastic materials, as well as one
process of incorporating elastic side panels into a training pant,
are described in the following U.S. Pat. Nos. 4,940,464 issued Jul.
10, 1990 to Van Gompel et al.; 5,224,405 issued Jul. 6, 1993 to
Pohjola; 5,104,116 issued Apr. 14, 1992 to Pohjola; and 5,046,272
issued Sep. 10, 1991 to Vogt et al.; all of which are incorporated
herein by reference. In particular embodiments, the elastic
material comprises a stretch-thermal laminate, a neck-bonded
laminate, a reversibly necked laminate, or a stretch-bonded
laminate material. Methods of making such materials are well known
to those skilled in the art and described in U.S. Pat. No.
4,663,220 issued May 5, 1987 to Wisneski et al.; U.S. Pat. No.
5,226,992 issued Jul. 13, 1993 to Morman; and European Patent
Application No. EP 0 217 032 published on Apr. 8, 1987 in the names
of Taylor et al.; all of which are incorporated herein by
reference. Alternatively, the side panel material may comprise
other woven or nonwoven materials, such as those described above as
being suitable for the outer cover 40 or body side liner 42;
mechanically prestrained materials; or extensible but inelastic
materials.
[0084] In particular embodiments, one or more of the side panels 34
and 134 can be formed of retractive materials. For example, the
side panels 34 and 134 can be formed of an elastomeric material
that is adapted to retract upon activation by a source of heat,
such as disclosed in U.S. Pat. No. 4,640,726.
[0085] The illustrated training pant 20 includes a fastening system
80 for refastenably securing the training pant about the waist of
the wearer. The illustrated fastening system 80 includes first
fastening components 82 and 83 that are adapted to refastenably
connect to mating second fastening components 84 and 85. In one
embodiment, one surface of each of the first fastening components
82 and 83 comprises a plurality of engaging elements that project
from that surface. The engaging elements of the first fastening
components 82 and 83 are adapted to repeatedly engage and disengage
engaging elements of the second fastening components 84 and 85.
[0086] In one particular embodiment, the first fastening components
82 and 83 each comprise hook type fasteners and the second
fastening components 84 and 85 each comprise complementary
fasteners formed of oriented nonwoven loop material. In another
particular embodiment, the first fastening components 82 and 83
each comprise fasteners formed of oriented nonwoven loop material
and the second fastening components 84 and 85 each comprise
complementary hook type fasteners. Although the illustrated
embodiments show the back waist region 24 overlapping the front
waist region 22, which is convenient, the training pant 20 can also
be configured so that the front waist region overlaps the back
waist region.
[0087] In alternative embodiments contemplated by this invention,
fasteners 82-85 can be located anywhere over the front or back
regions 22 and 24 of the pant. The fasteners 82-85 can be integral
to any of the materials on the pant in the front or back regions 22
and 24. The fasteners can be integral to the entire outer cover of
the pant (e.g. in a one piece outer cover product) or integral to
the entire liner in the pant. The fasteners can be integral to
panels 34 and/or 134.
[0088] Hook type fasteners typically comprise a fabric or material
having a base or backing structure and a plurality of hook members
extending upwardly from at least one surface of the backing
structure. The hook material advantageously comprises a resilient
material to minimize unintentional disengagement of the fastener
components as a result of the hook material becoming deformed and
catching on clothing or other items. The term "resilient" as used
herein refers to an interlocking material having a predetermined
shape and the property of the interlocking material to resume the
predetermined shape after being engaged and disengaged from a
mating, complementary interlocking material. Suitable hook material
can be molded or extruded of nylon, polypropylene or another
suitable material. Suitable single-sided hook materials for the
fastening components 82-85 are available from commercial vendors
such as Velcro Industries B.V., Amsterdam, Netherlands or
affiliates thereof, and are identified as Velcro HTH-829 with a
unidirectional hook pattern and having a thickness of about 0.9
millimeters (35 mils) and HTH-851 with a unidirectional hook
pattern and having a thickness of about 0.5 millimeters (20 mils);
and Minnesota Mining & Manufacturing Co., St. Paul, Minn.
U.S.A., including specific materials identified as CS-600.
[0089] In accordance with the present invention, the loop type
fastener is preferably made of an oriented material, and more
preferably an oriented material comprising a nonwoven web of
substantially continuous fibers. In particular embodiments, the
oriented material can comprise an oriented, extensible material,
and particularly, an oriented, extensible material attached to an
elastic substrate so that the composite is extensible and provides
retraction tension over a suitable range of extensions. With
particular reference to FIG. 3, the first fastening components 82
and 83 are desirably although not necessarily disposed on the inner
surface 28 of the training pant 20 in the back waist region 24. The
first fastening components 82 and 83 are desirably positioned along
the distal edges 68 of the back side panels 134, and abutting or
adjacent to the waist end edge 72. In certain embodiments, for
example, the first fastening components 82 and 83 can be located
within about 2 centimeters, and more particularly within about 1
centimeter, of the distal edges 68, the waist end edges 72, and the
leg end edges 70.
[0090] With particular reference to FIG. 2, the second fastening
components 84 and 85 are desirably although not necessarily
disposed on the outer surface 30 of the training pant 20 in the
front waist region 22. The second fastening components 84 and 85
are sized to receive the first fastening components 82 and 83 and
are desirably positioned along the distal edges 68 of the front
side panels 34, and abutting or adjacent to the waist end edge 72.
In certain embodiments, for example, the second fastening
components 84 and 85 can be located within about 2 centimeters, and
more particularly within about 1 centimeter, of the distal edges
68, the waist end edges 72, and the leg end edges 70. Where the
first fastening components 82 and 83 comprise loop type fasteners
disposed on the inner surface 28 and the second fastening
components 84 and 85 comprise hook type fasteners disposed on the
outer surface 30, the first fastening components can be sized
larger than the second fastening components to ensure coverage of
the rigid, outwardly-directed hooks. The loop fastening components
can be integral with the side panels or adhered to the side panels
34 and 134 by any means known to those skilled in the art such as
adhesive bonds, sonic bonds or thermal bonds. The loop fastening
components can be extensible and bonded in overlaying relationship
onto any layer of the body 32 in a manner that retains the
extension and retraction characteristics of the loop fastening
components.
[0091] The fastening components are desirably rectangular, although
they may alternatively be square, round, oval, curved or otherwise
non-rectangular in shape. In particular embodiments, each of the
fastening components 82-85 defines a length dimension aligned
generally parallel with the longitudinal axis 48 of the training
pant 20 and a width dimension aligned generally parallel with the
transverse axis 49 of the training pant. For a child of about 9 to
about 15 kilograms (20-33 pounds), for example, the length
dimension of the fastening components is desirably from about 5 to
about 13 centimeters, such as about 10 centimeters, and the width
dimension is desirably from about 0.5 to about 3 centimeters, such
as about 1 centimeter. With particular embodiments, the fastening
components can have a length-to-width ratio of about 2 or greater,
such as about 2 to about 25, and particularly about 5 or greater,
such as about 5 to about 8. For other embodiments such as for adult
products, it may be desirable for one or more of the fastening
components to comprise a plurality of relatively smaller fastening
elements. In that case, a fastening component or individual
fastening elements may have an even smaller length-to-width ratio,
for example, of about 2 or less, and even about 1 or less.
[0092] When the fastening components 82-85 are releasably engaged,
the side edges 36 of the absorbent body 32 in the crotch region 26
define the leg openings 52, the waist edges 38 and 39 of the
absorbent body, including the waist end edges 72 of the side
panels, define the waist opening 50, and the waist regions 22 and
24 jointly define a waistband 75 and hip section 77. For improved
formation of the leg openings 52, it can be desirable in some
embodiments for the front side panels 34 to be longitudinally
spaced from the back side panels 134 (see FIGS. 2 and 3). For
example, the front side panels 34 can be longitudinally spaced from
the back side panels 134 by a distance equal to about 20 percent or
greater, particularly from about 20 to about 60 percent, and more
particularly from about 35 to about 50 percent, of the overall
length dimension of the absorbent article.
[0093] When connected, the fastening components 82-85 form
refastenable seams 88 (FIG. 1) that desirably although not
necessarily extend substantially the entire distance between the
waist opening 50 and the leg openings 52. More specifically, the
refastenable seams 88 can cover about 80 to 100 percent, and
particularly about 90 to about 98 percent, of the distance between
the waist opening 50 and each leg opening 52, which distance is
measured parallel to the longitudinal axis 48. To construct the
seams 88 to extend substantially the entire distance between the
waist and leg openings 50 and 52, the fastening components 82-85
can be formed to cover about 80 to 100 percent, and more
particularly about 90 to about 98 percent, of the distance between
the waist end edge 70 and the leg end edge 72 of the side panels 34
and 134. In other embodiments, the fastening components can
comprise a plurality of smaller fastening elements covering a
smaller portion of the distance between the waist opening 50 and
the leg openings 52, for example, about 20 to about 70 percent, but
spaced apart to span a larger percentage of the distance between
the waist opening and the leg openings.
[0094] It is also contemplated that the fastening components 82-85
may be incorporated as integral portions of the pant rather than
separate components applied during manufacture. If the fastening
components 82 and 83, are a single component and are integral to
the pant in the front region 22, for example, the size and the
shape of the fastening component is directly equal to the size and
shape of that region. If the fastening components 82-85 are
integral parts of side panels 34 and/or 134, for another example,
the fastening components are the same size and shape as the side
panels 34 and/or 134.
[0095] For the refastenable seams 88 to be located at the sides of
the wearer, it can be particularly desirable for the transverse
distance between the first fastening components 82 and 83 to be
substantially equal to the transverse distance between the second
fastening components 84 and 85. The transverse distance between a
set of fasteners is the distance measured parallel to the
transverse axis 49 between the longitudinal centerlines of the
fasteners, measured with the side panels 34 and 134 in their
relaxed, or non-extended, condition. In an alternative embodiment,
the training pant 20 includes only a single second fastening
component disposed in the front waist region 22 for refastenably
connecting the first fastening components 82 and 83 (not
shown).
[0096] In a further alternative embodiment illustrated in FIGS. 4
and 5, one or both of the fastening components can comprise
integral portions of the waist regions. For instance, the front and
back side panels 34 and 134 can function as fastening components in
that they can comprise a material that is releasably engageable
with complementary fastening components disposed in the opposite
waist region. As illustrated in FIGS. 4 and 5, the side panels 134
are made completely of extensible oriented loop material.
Alternatively, these side panels could be made of oriented loop
material only at their outer edges where they will engage the hook
material, and the remainder of the side panels can be made of some
other, preferably extensible, material and joined along abutting
edges thereof.
[0097] FIG. 6 schematically shows how a nonwoven can be drawn
between two nips to orient the material. This drawing process also
orients the fibers in the machine direction. Specifically, the
drawing process of FIG. 6 orients the nonwoven in the machine
direction. This drawing process also orients the nonwoven fibers to
be more aligned in the machine direction than in the cross
direction. A nonwoven material, illustrated in FIG. 6 as roll A, of
a certain width is fed into a nip point or a draw control section,
as illustrated in FIG. 6 as nip B. The draw control point B is
running at a speed of x and controls the speed of the feeding
nonwoven web. The nonwoven material is than drawn to a nip point or
draw control point C. Draw control point C is running faster than
draw control point B, which orients the nonwoven. The ratio of the
speed of nip C to the speed of nip B is the draw ratio between the
two nips. If the distance between nips B and C is relatively small,
the drawing process does not substantially narrow, or neck, the
web. If the distance between nips B and C is relatively large, the
drawing process can narrow, or neck, the material in the cross
direction to a greater extent. By adding nip points subsequent to
nip C, the material can be oriented and/or necked further. By
controlling the distance between nips B and C and subsequent nips
and the draw ratios between the nip points, the degree of
orientation of the web in the machine direction and the degree of
necking of the web in the cross direction can be controlled. The
nonwoven material thus oriented can be wound on a base roll or
attached by bonder I to another material H. The bonding can be
accomplished by hot melt adhesive, ultrasonic bonds, thermal bonds,
or any means well known in the art of bonding. Attachment to a
substrate may also be accomplished by direct extrusion of a
substrate polymer onto the extended nonwoven, or by means of
calendering an extruded substrate directly to the extended nonwoven
in a heated and/or patterned nip. The nonwoven can be wound to form
a base roll D to later be unwound into another assembly process
(such as making a disposable training pant). Alternatively, this
process for producing the oriented nonwoven loop material can be an
integral step in the assembling process for making a disposable
training pant.
[0098] FIG. 7 schematically shows how a nonwoven can be drawn in
the cross machine direction to orient the material and its
constituent fibers in the cross machine direction. Thus, the cross
machine direction drawing process illustrated in FIG. 7 orients the
nonwoven in the cross machine direction and orients the fibers of
the nonwoven in the cross machine direction. A nonwoven E is
unwound or fed into a side stretching section F. This side
stretching section grips the side edges of the nonwoven and draws
or extends the material in the cross machine direction as it moves
in the machine direction of the drawing process. Side stretching
section F may consist of multiple, sequential side stretching
subsections. The nonwoven material can then be wound on a roll G,
or fed into another process such as a disposable pant assembly
process, or laminated to another material to stabilize the
orientation of the fibers in the cross machine direction.
[0099] The orientable material used to form the oriented nonwoven
loop material can be made in accordance with the teachings of U.S.
Pat. No. 4,965,122 incorporated herein by reference thereto. The
orientable material may be formed by known nonwoven processes, such
as, for example, meltblowing processes or spunbonding processes. If
the orientable material is a web of meltblown fibers, it may
include meltblown microfibers. The orientable material can be any
material with a network of substantially continuous fibers or
filaments that can be oriented upon application of a force in one
direction without material failure, i.e., breaking or tearing.
[0100] The orientable material could be a multilayer material
having, for example, at least one layer of spunbonded web joined to
at least one layer of meltblown web, bonded carded web or other
suitable material. For example, the orientable material may be a
multilayer material having a first layer of spunbonded
polypropylene having a basis weight from about 0.2 to about 8
ounces per square yard (osy), a layer of meltblown polypropylene
having a basis weight from about 0.2 to about 4 osy, and a second
layer of spunbonded polypropylene having a basis weight of about
0.2 to about 8 osy. Alternatively, the orientable material may be a
single layer of material such as, for example, a spunbonded web
having a basis weight of from about 0.2 to about 10 osy or a
meltblown web having a basis weight of from about 0.2 to about 8
osy.
[0101] The orientable material may also be a composite material
made of a mixture of two or more different fibers or a mixture of
fibers and particulates. Such mixtures may be formed by adding
fibers and/or particulates to a gas stream in which meltblown
fibers are carried so that an intimate entangled commingling of
substantially continuous meltblown fibers and other materials,
e.g., wood pulp, staplefibers or particulates such as, for example,
super-absorbent materials, occurs prior to collection of the fibers
upon a collecting device to form a coherent web of randomly
dispersed meltblown fibers and other materials, such as are
disclosed in U.S. Pat. No. 4,100,324, the disclosure of which is
hereby incorporated by reference.
[0102] If the orientable material is a nonwoven web of fibers, the
fibers should be joined by interfiber bonding to form a coherent
web structure which is able to withstand orienting. Interfiber
bonding may be produced by entanglement between individual fibers.
The fiber entangling is inherent in the meltblown process but may
be generated or increased by processes such as, for example,
hydraulic entangling or needle punching. Alternatively and/or
additionally a bonding agent may be used to increase the desired
bonding.
[0103] The oriented material may be stabilized if desired by one of
a number of methods. Application of heat can be used to produce a
"set" in a necked, oriented material, which provides a loop
material that readily extends but has little retractive force upon
extension. Alternatively, the oriented material may be attached to
an extendable substrate, such as a film, with provides a loop
material requiring somewhat greater force to extend, but will not
retract after extension. If a non-extensible loop material is
desired, the oriented material may be attached to a non-extensible
substrate. If an elastic loop material having both extension and
recovery characteristics normally associated with elastomeric
materials is desired, an oriented, necked material should be
attached to an elastic substrate.
[0104] The oriented material can be made into a neck-bonded
laminate as taught in U.S. Pat. No. 4,981,747. The oriented
material may be treated if it has been necked in the drawing
process to instill a memory into the material to cause the material
to retract from its extension as taught in U.S. Pat. No. 4,965,122.
A method of treatment is the application of heat. Certain polymers
such as, for example, polyolefins, polyesters and polyamides may be
heat treated under suitable conditions to impart such memory.
Exemplary polyolefins include one or more of polyethylene,
polypropylene, polybutene, ethylene copolymers, propylene
copolymers and butene copolymers. Polypropylenes that have been
found useful include, for example, polypropylene available from the
Himont Corporation under the trade designation PC-973,
polypropylene available from the Exxon Chemical Company under the
trade designation Exxon 3445, and polypropylene available from the
Shell Chemical Company under the trade designation DX 5A09.
Chemical characteristics of these materials are available from
their respective manufacturers.
[0105] The relation between the original width of the orientable
material to its width after tensioning determines the extension
limits of the oriented material. For example, if it is desired to
prepare a necked material that can be readily extended to a 150
percent elongation (i.e., 250 percent of its necked width) an
orientable material having a width "A" such as, for example, 250
cm, is tensioned so that it necks down to a width "B" of about 100
cm for a percent neck or percent neckdown of about 60 percent. The
resulting necked material has a width "B" of about 100 cm and is
readily extensible to at least the original 250 cm dimension "A" of
the orientable material for an elongation or percent stretch of
about 150 percent. The necked material can be made into neck-bonded
laminate material by laminating the necked material to an elastomer
as taught in U.S. Pat. No. 5,336,545.
[0106] It is also contemplated that when the training pants or the
like garment are being initially constructed and folded by machine,
the loop material and/or its underlying support material of the
various embodiments can be positioned over the hook material and
then pressed thereon to give an initial construction that is
stronger in the mechanical fastener system than conventional
mechanical fastening systems.
[0107] While the mechanical fastening means of the present
invention are shown and described herein in connection with
children's toilet training pants, it is understood that such
fastening means may be incorporated into various other disposable
absorbent articles, such as diapers, adult incontinence garments,
sanitary napkins and the like, as well as surgical bandages and
sponges, without departing from the scope of the present
invention.
[0108] As various changes could be made in the above constructions
and methods, without departing from the scope of the invention, it
is intended that all matter contained in the above description and
shown in the accompanying drawings shall be interpreted as
illustrative and not in a limiting sense.
[0109] When introducing elements of the present invention or the
preferred embodiment(s) thereof, the articles "a", "an", "the" and
"said" are intended to mean that there are one or more of the
elements. The terms "comprising", "including" and "having" are
intended to be inclusive and mean that there may be additional
elements other than the listed elements.
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